As the shared animal/tissue resource for the Program Project, our goals will be to: a) in year 01-05, produce and supply for the four projects, two strains of adventitious-pathogen-free inbred SENCAR-derived mice, the SSIN/UTSP/Vsp mouse and the Line C mouse. b) in years 01 and 02, we will conduct the specified tumor experiments in both of these inbred strains and in the outbred SENCAR mouse (available commercially) and in coordination with Core (Histopathology and Tissue Analysis Shared Resource), supply both fresh and preserved tumor tissue to the project leaders. c) in years 03-05, we will maintain up to four lines of transgenic mice for the project leaders. We will be responsible for care and husbandry, for assuring genetic integrity of the lines, and for producing the mice in sufficient numbers for biochemical, histological and tumor experiments as outlined by the investigators. d) the mice held and produced by us, as well as the outbred SENCAR mice purchased for use in tumor experiments, will be held in pathogen-free facilities monitored regularly for the presence of infectious diseases or parasites that could potentially interfere with the objectives of the four projects. The genetic authenticity of the inbred lines will ensured by appropriate breeding practices and safeguards. Biochemical marker analysis of at least 12 loci will be performed regularly by a commercial laboratory. Transgenic mouse verification will be performed regularly by project leaders with appropriate assays specific for the transgene.